Deprecate FLAGS_quic_do_not_send_ack_on_emsgsize.

net/quic/core/quic_flags_list.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file intentionally does not have header guards, it's included
 // inside a macro to generate values.
 
 // This file contains the list of QUIC protocol flags.
 
 // If true, QUIC BBR congestion control may be enabled via Finch and/or via QUIC
@@ skipping 84 matching lines @@
 QUIC_FLAG(bool, FLAGS_quic_disable_pre_32, true)
 
 // If true, QUIC will enforce the MTU limit for connections that may require a
 // small MTU.
 QUIC_FLAG(bool, FLAGS_quic_enforce_mtu_limit, false)
 
 // Disable MTU probing if MTU probe causes ERR_MSG_TOO_BIG instead of aborting
 // the connection.
 QUIC_FLAG(bool, FLAGS_graceful_emsgsize_on_mtu_probe, true)
 
-// If true, do not force sending ack when connection is closed because of
-// message too long (EMSGSIZE) write error.
-QUIC_FLAG(bool, FLAGS_quic_do_not_send_ack_on_emsgsize, true)
-
 // If true, set a QUIC connection's last_sent_for_timeout_ to the send time of
 // the first packet sent after receiving a packet, even if the sent packet is
 // a retransmission
 QUIC_FLAG(bool, FLAGS_quic_better_last_send_for_timeout, true)
 
 // If true, send an explicit TTL in QUIC REJ messages to mitigate client clock
 // skew.
 QUIC_FLAG(bool, FLAGS_quic_send_scfg_ttl, true)
 
 // If true, only open limited number of quic sessions per epoll event. Leave the
 // rest to next event. This flag can be turned on only if
 // --quic_buffer_packet_till_chlo is true.
 QUIC_FLAG(bool, FLAGS_quic_limit_num_new_sessions_per_epoll_loop, false)
 
 // If true, lazy allocate and early release memeory used in
 // QuicStreamSequencerBuffer to buffer incoming data.
 QUIC_FLAG(bool, FLAGS_quic_reduce_sequencer_buffer_memory_life_time, true)
 
 // If true, allow server address change if it is because of mapped ipv4 address.
 QUIC_FLAG(bool, FLAGS_quic_allow_server_address_change_for_mapped_ipv4, true)
 
 // If true, disables QUIC version less than 34.
 QUIC_FLAG(bool, FLAGS_quic_disable_pre_34, false)
 
 // When true, decode the packet number from the largest received packet, rather
 // than the most recent.
 QUIC_FLAG(bool, FLAGS_quic_packet_numbers_largest_received, true)